Add fields to DHCP packets for server use-case (1885805a) · Commits · e / os / android_frameworks_base

services/net/java/android/net/dhcp/DhcpDiscoverPacket.java

+11 −4

Original line number	Diff line number	Diff line
		@@ -23,11 +23,18 @@ import java.nio.ByteBuffer;
		* This class implements the DHCP-DISCOVER packet.
		*/
		class DhcpDiscoverPacket extends DhcpPacket {
		/**
		* The IP address of the client which sent this packet.
		*/
		final Inet4Address mSrcIp;

		/**
		* Generates a DISCOVER packet with the specified parameters.
		*/
		DhcpDiscoverPacket(int transId, short secs, byte[] clientMac, boolean broadcast) {
		super(transId, secs, INADDR_ANY, INADDR_ANY, INADDR_ANY, INADDR_ANY, clientMac, broadcast);
		DhcpDiscoverPacket(int transId, short secs, Inet4Address relayIp, byte[] clientMac,
		boolean broadcast, Inet4Address srcIp) {
		super(transId, secs, INADDR_ANY, INADDR_ANY, INADDR_ANY, relayIp, clientMac, broadcast);
		mSrcIp = srcIp;
		}

		public String toString() {
		@@ -41,8 +48,8 @@ class DhcpDiscoverPacket extends DhcpPacket {
		*/
		public ByteBuffer buildPacket(int encap, short destUdp, short srcUdp) {
		ByteBuffer result = ByteBuffer.allocate(MAX_LENGTH);
		fillInPacket(encap, INADDR_BROADCAST, INADDR_ANY, destUdp,
		srcUdp, result, DHCP_BOOTREQUEST, mBroadcast);
		fillInPacket(encap, INADDR_BROADCAST, mSrcIp, destUdp, srcUdp, result, DHCP_BOOTREQUEST,
		mBroadcast);
		result.flip();
		return result;
		}

services/net/java/android/net/dhcp/DhcpNakPacket.java

+7 −9

Original line number	Diff line number	Diff line
		@@ -26,11 +26,9 @@ class DhcpNakPacket extends DhcpPacket {
		/**
		* Generates a NAK packet with the specified parameters.
		*/
		DhcpNakPacket(int transId, short secs, Inet4Address clientIp, Inet4Address yourIp,
		Inet4Address nextIp, Inet4Address relayIp,
		byte[] clientMac) {
		super(transId, secs, INADDR_ANY, INADDR_ANY, nextIp, relayIp,
		clientMac, false);
		DhcpNakPacket(int transId, short secs, Inet4Address nextIp, Inet4Address relayIp,
		byte[] clientMac, boolean broadcast) {
		super(transId, secs, INADDR_ANY, INADDR_ANY, nextIp, relayIp, clientMac, broadcast);
		}

		public String toString() {
		@@ -43,11 +41,11 @@ class DhcpNakPacket extends DhcpPacket {
		*/
		public ByteBuffer buildPacket(int encap, short destUdp, short srcUdp) {
		ByteBuffer result = ByteBuffer.allocate(MAX_LENGTH);
		Inet4Address destIp = mClientIp;
		Inet4Address srcIp = mYourIp;
		// Constructor does not set values for layers <= 3: use empty values
		Inet4Address destIp = INADDR_ANY;
		Inet4Address srcIp = INADDR_ANY;

		fillInPacket(encap, destIp, srcIp, destUdp, srcUdp, result,
		DHCP_BOOTREPLY, mBroadcast);
		fillInPacket(encap, destIp, srcIp, destUdp, srcUdp, result, DHCP_BOOTREPLY, mBroadcast);
		result.flip();
		return result;
		}

services/net/java/android/net/dhcp/DhcpPacket.java

+71 −31

Original line number	Diff line number	Diff line
		package android.net.dhcp;

		import android.annotation.Nullable;
		import android.net.DhcpResults;
		import android.net.LinkAddress;
		import android.net.NetworkUtils;
		@@ -204,6 +205,7 @@ public abstract class DhcpPacket {
		protected static final byte DHCP_MESSAGE_TYPE_DECLINE = 4;
		protected static final byte DHCP_MESSAGE_TYPE_ACK = 5;
		protected static final byte DHCP_MESSAGE_TYPE_NAK = 6;
		protected static final byte DHCP_MESSAGE_TYPE_RELEASE = 7;
		protected static final byte DHCP_MESSAGE_TYPE_INFORM = 8;

		/**
		@@ -252,6 +254,7 @@ public abstract class DhcpPacket {
		* DHCP Optional Type: DHCP Client Identifier
		*/
		protected static final byte DHCP_CLIENT_IDENTIFIER = 61;
		protected byte[] mClientId;

		/**
		* DHCP zero-length option code: pad
		@@ -281,7 +284,7 @@ public abstract class DhcpPacket {
		protected final Inet4Address mClientIp;
		protected final Inet4Address mYourIp;
		private final Inet4Address mNextIp;
		private final Inet4Address mRelayIp;
		protected final Inet4Address mRelayIp;

		/**
		* Does the client request a broadcast response?
		@@ -338,13 +341,28 @@ public abstract class DhcpPacket {
		return mClientMac;
		}

		// TODO: refactor DhcpClient to set clientId when constructing packets and remove
		// hasExplicitClientId logic
		/**
		* Returns the client ID. This follows RFC 2132 and is based on the hardware address.
		* Returns whether a client ID was set in the options for this packet.
		*/
		public boolean hasExplicitClientId() {
		return mClientId != null;
		}

		/**
		* Returns the client ID. If not set explicitly, this follows RFC 2132 and creates a client ID
		* based on the hardware address.
		*/
		public byte[] getClientId() {
		byte[] clientId = new byte[mClientMac.length + 1];
		final byte[] clientId;
		if (hasExplicitClientId()) {
		clientId = Arrays.copyOf(mClientId, mClientId.length);
		} else {
		clientId = new byte[mClientMac.length + 1];
		clientId[0] = CLIENT_ID_ETHER;
		System.arraycopy(mClientMac, 0, clientId, 1, mClientMac.length);
		}
		return clientId;
		}

		@@ -531,8 +549,10 @@ public abstract class DhcpPacket {

		/**
		* Adds an optional parameter containing an array of bytes.
		*
		* <p>This method is a no-op if the payload argument is null.
		*/
		protected static void addTlv(ByteBuffer buf, byte type, byte[] payload) {
		protected static void addTlv(ByteBuffer buf, byte type, @Nullable byte[] payload) {
		if (payload != null) {
		if (payload.length > MAX_OPTION_LEN) {
		throw new IllegalArgumentException("DHCP option too long: "
		@@ -546,8 +566,10 @@ public abstract class DhcpPacket {

		/**
		* Adds an optional parameter containing an IP address.
		*
		* <p>This method is a no-op if the address argument is null.
		*/
		protected static void addTlv(ByteBuffer buf, byte type, Inet4Address addr) {
		protected static void addTlv(ByteBuffer buf, byte type, @Nullable Inet4Address addr) {
		if (addr != null) {
		addTlv(buf, type, addr.getAddress());
		}
		@@ -555,8 +577,10 @@ public abstract class DhcpPacket {

		/**
		* Adds an optional parameter containing a list of IP addresses.
		*
		* <p>This method is a no-op if the addresses argument is null or empty.
		*/
		protected static void addTlv(ByteBuffer buf, byte type, List<Inet4Address> addrs) {
		protected static void addTlv(ByteBuffer buf, byte type, @Nullable List<Inet4Address> addrs) {
		if (addrs == null \|\| addrs.size() == 0) return;

		int optionLen = 4 * addrs.size();
		@@ -574,9 +598,11 @@ public abstract class DhcpPacket {
		}

		/**
		* Adds an optional parameter containing a short integer
		* Adds an optional parameter containing a short integer.
		*
		* <p>This method is a no-op if the value argument is null.
		*/
		protected static void addTlv(ByteBuffer buf, byte type, Short value) {
		protected static void addTlv(ByteBuffer buf, byte type, @Nullable Short value) {
		if (value != null) {
		buf.put(type);
		buf.put((byte) 2);
		@@ -585,9 +611,11 @@ public abstract class DhcpPacket {
		}

		/**
		* Adds an optional parameter containing a simple integer
		* Adds an optional parameter containing a simple integer.
		*
		* <p>This method is a no-op if the value argument is null.
		*/
		protected static void addTlv(ByteBuffer buf, byte type, Integer value) {
		protected static void addTlv(ByteBuffer buf, byte type, @Nullable Integer value) {
		if (value != null) {
		buf.put(type);
		buf.put((byte) 4);
		@@ -597,14 +625,18 @@ public abstract class DhcpPacket {

		/**
		* Adds an optional parameter containing an ASCII string.
		*
		* <p>This method is a no-op if the string argument is null.
		*/
		protected static void addTlv(ByteBuffer buf, byte type, String str) {
		protected static void addTlv(ByteBuffer buf, byte type, @Nullable String str) {
		if (str != null) {
		try {
		addTlv(buf, type, str.getBytes("US-ASCII"));
		} catch (UnsupportedEncodingException e) {
		throw new IllegalArgumentException("String is not US-ASCII: " + str);
		}
		}
		}

		/**
		* Adds the special end-of-optional-parameters indicator.
		@@ -740,6 +772,7 @@ public abstract class DhcpPacket {
		Inet4Address nextIp;
		Inet4Address relayIp;
		byte[] clientMac;
		byte[] clientId = null;
		List<Inet4Address> dnsServers = new ArrayList<>();
		List<Inet4Address> gateways = new ArrayList<>(); // aka router
		Inet4Address serverIdentifier = null;
		@@ -1038,8 +1071,8 @@ public abstract class DhcpPacket {
		throw new ParseException(DhcpErrorEvent.DHCP_NO_MSG_TYPE,
		"No DHCP message type option");
		case DHCP_MESSAGE_TYPE_DISCOVER:
		newPacket = new DhcpDiscoverPacket(
		transactionId, secs, clientMac, broadcast);
		newPacket = new DhcpDiscoverPacket(transactionId, secs, relayIp, clientMac,
		broadcast, ipSrc);
		break;
		case DHCP_MESSAGE_TYPE_OFFER:
		newPacket = new DhcpOfferPacket(
		@@ -1047,7 +1080,7 @@ public abstract class DhcpPacket {
		break;
		case DHCP_MESSAGE_TYPE_REQUEST:
		newPacket = new DhcpRequestPacket(
		transactionId, secs, clientIp, clientMac, broadcast);
		transactionId, secs, clientIp, relayIp, clientMac, broadcast);
		break;
		case DHCP_MESSAGE_TYPE_DECLINE:
		newPacket = new DhcpDeclinePacket(
		@@ -1060,8 +1093,15 @@ public abstract class DhcpPacket {
		break;
		case DHCP_MESSAGE_TYPE_NAK:
		newPacket = new DhcpNakPacket(
		transactionId, secs, clientIp, yourIp, nextIp, relayIp,
		clientMac);
		transactionId, secs, nextIp, relayIp, clientMac, broadcast);
		break;
		case DHCP_MESSAGE_TYPE_RELEASE:
		if (serverIdentifier == null) {
		throw new ParseException(DhcpErrorEvent.MISC_ERROR,
		"DHCPRELEASE without server identifier");
		}
		newPacket = new DhcpReleasePacket(
		transactionId, serverIdentifier, clientIp, relayIp, clientMac);
		break;
		case DHCP_MESSAGE_TYPE_INFORM:
		newPacket = new DhcpInformPacket(
		@@ -1074,6 +1114,7 @@ public abstract class DhcpPacket {
		}

		newPacket.mBroadcastAddress = bcAddr;
		newPacket.mClientId = clientId;
		newPacket.mDnsServers = dnsServers;
		newPacket.mDomainName = domainName;
		newPacket.mGateways = gateways;
		@@ -1173,8 +1214,8 @@ public abstract class DhcpPacket {
		*/
		public static ByteBuffer buildDiscoverPacket(int encap, int transactionId,
		short secs, byte[] clientMac, boolean broadcast, byte[] expectedParams) {
		DhcpPacket pkt = new DhcpDiscoverPacket(
		transactionId, secs, clientMac, broadcast);
		DhcpPacket pkt = new DhcpDiscoverPacket(transactionId, secs, INADDR_ANY /* relayIp */,
		clientMac, broadcast, INADDR_ANY /* srcIp */);
		pkt.mRequestedParams = expectedParams;
		return pkt.buildPacket(encap, DHCP_SERVER, DHCP_CLIENT);
		}
		@@ -1223,12 +1264,11 @@ public abstract class DhcpPacket {
		/**
		* Builds a DHCP-NAK packet from the required specified parameters.
		*/
		public static ByteBuffer buildNakPacket(int encap, int transactionId,
		Inet4Address serverIpAddr, Inet4Address clientIpAddr, byte[] mac) {
		DhcpPacket pkt = new DhcpNakPacket(transactionId, (short) 0, clientIpAddr,
		serverIpAddr, serverIpAddr, serverIpAddr, mac);
		pkt.mMessage = "requested address not available";
		pkt.mRequestedIp = clientIpAddr;
		public static ByteBuffer buildNakPacket(int encap, int transactionId, Inet4Address serverIpAddr,
		byte[] mac, boolean broadcast, String message) {
		DhcpPacket pkt = new DhcpNakPacket(
		transactionId, (short) 0, serverIpAddr, serverIpAddr, mac, broadcast);
		pkt.mMessage = message;
		return pkt.buildPacket(encap, DHCP_CLIENT, DHCP_SERVER);
		}

		@@ -1240,7 +1280,7 @@ public abstract class DhcpPacket {
		byte[] clientMac, Inet4Address requestedIpAddress,
		Inet4Address serverIdentifier, byte[] requestedParams, String hostName) {
		DhcpPacket pkt = new DhcpRequestPacket(transactionId, secs, clientIp,
		clientMac, broadcast);
		INADDR_ANY /* relayIp */, clientMac, broadcast);
		pkt.mRequestedIp = requestedIpAddress;
		pkt.mServerIdentifier = serverIdentifier;
		pkt.mHostName = hostName;

services/net/java/android/net/dhcp/DhcpReleasePacket.java

0 → 100644

+58 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2018 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		package android.net.dhcp;

		import java.net.Inet4Address;
		import java.nio.ByteBuffer;

		/**
		* Implements DHCP-RELEASE
		*/
		class DhcpReleasePacket extends DhcpPacket {

		final Inet4Address mClientAddr;

		/**
		* Generates a RELEASE packet with the specified parameters.
		*/
		public DhcpReleasePacket(int transId, Inet4Address serverId, Inet4Address clientAddr,
		Inet4Address relayIp, byte[] clientMac) {
		super(transId, (short)0, clientAddr, INADDR_ANY /* yourIp /, INADDR_ANY / nextIp */,
		relayIp, clientMac, false /* broadcast */);
		mServerIdentifier = serverId;
		mClientAddr = clientAddr;
		}


		@Override
		public ByteBuffer buildPacket(int encap, short destUdp, short srcUdp) {
		ByteBuffer result = ByteBuffer.allocate(MAX_LENGTH);
		fillInPacket(encap, mServerIdentifier /* destIp /, mClientIp / srcIp */, destUdp, srcUdp,
		result, DHCP_BOOTREPLY, mBroadcast);
		result.flip();
		return result;
		}

		@Override
		void finishPacket(ByteBuffer buffer) {
		addTlv(buffer, DHCP_MESSAGE_TYPE, DHCP_MESSAGE_TYPE_RELEASE);
		addTlv(buffer, DHCP_CLIENT_IDENTIFIER, getClientId());
		addTlv(buffer, DHCP_SERVER_IDENTIFIER, mServerIdentifier);
		addCommonClientTlvs(buffer);
		addTlvEnd(buffer);
		}
		}

services/net/java/android/net/dhcp/DhcpRequestPacket.java

+3 −3

Original line number	Diff line number	Diff line
		@@ -28,9 +28,9 @@ class DhcpRequestPacket extends DhcpPacket {
		/**
		* Generates a REQUEST packet with the specified parameters.
		*/
		DhcpRequestPacket(int transId, short secs, Inet4Address clientIp, byte[] clientMac,
		boolean broadcast) {
		super(transId, secs, clientIp, INADDR_ANY, INADDR_ANY, INADDR_ANY, clientMac, broadcast);
		DhcpRequestPacket(int transId, short secs, Inet4Address clientIp, Inet4Address relayIp,
		byte[] clientMac, boolean broadcast) {
		super(transId, secs, clientIp, INADDR_ANY, INADDR_ANY, relayIp, clientMac, broadcast);
		}

		public String toString() {